More American households are falling back into the debt hole — this time without the safety net of home values to help bail them out.

Last year, total US consumer debt reached the highest point in a decade, according to a credit-card industry observer.

“Now more than ever, families need to work at saving and paying off any outstanding debts,” says Howard Dvorkin, a CPA and founder of ConsolidatedCredit.org, a credit counseling service.

He says that, after a few months of reducing credit-card debt levels, Americans are starting to return to their reliance on debt.

“People made some progress in reducing card debt earlier in the year, but in the last few months, as the stock market started to rise, they started to return to their old ways of charging things,” Dvorkin says.

In December, the total consumer debt, which is the combination of non-revolving and revolving debt, rose by some 9.3 percent to $2.498 trillion, according to the latest Federal Reserve Board numbers.

Both revolving debt and non-revolving debt increased. Revolving debt, which is credit-card debt, went up by 4.1 percent. Non-revolving debt, which includes loans for cars and education, rose 11.8 percent, the central bank’s report said.

The trend — month to month, quarter to quarter and year to year — is rising steeply.

“Consumer credit increased at an annual rate of 7.5 percent in the fourth quarter. Revolving credit increased at an annual rate of 4.5 percent, and non-revolving credit increased 9 percent in December,” the Fed wrote in a note along with the latest monthly report, which also reviewed 2011.

These numbers, Dvorkin warns, mean that many middle-class Americans are taking big risks.

In a weak economy, Dvorkin notes, with high unemployment, many people with big card balances become vulnerable to financial catastrophe.

Lewis J. Altfest, a Manhattan adviser who targets the professional, high-income client, devotes part of his practice to telling the well-heeled how to cut back on credit-card debt.

“It’s still a big problem. Some people want to live life to the fullest even though they are using their cards too much,” Altfest explains. He says many clients last year tried to reduce card debt. But some “are falling back into their old ways.”

Indeed, last holiday season many consumers financed Black Friday trips to the mall and Cyber Monday online buying sprees by making purchases with plastic, Dvorkin contends.

“As the bills begin to roll in, consumers may find themselves unable to pay them off. It’s good to see an increase in consumer spending, but never is it worth going into debt,” according to Dvorkin.

What should people do who were carried away by the holiday spirit?

Advisers say that starting to pay down debt should be the top financial priority, trumping both saving and consumption. And don’t add any new debt, they say.